BOZEMAN — Universities were among the first participants in the long-distance computer network now called the internet, playing an important role in demonstrating and developing the technology in the 1970s. Now, with a $6 million research contract, Montana State University is poised to contribute to one of the internet’s biggest advances since its creation.
The two-year funding from the Air Force Research Laboratory will support a team of MSU researchers as part of an international effort to develop what’s called the quantum internet, which harnesses the complex properties of light to interconnect quantum computers and improve speed and security.
“We’re looking a decade or more ahead, and this is where the internet is going,” said project leader John Roudas, professor in the Department of Electrical and Computer Engineering in MSU’s Norm Asbjornson College of Engineering. “This is a very good opportunity for MSU to play a leading role in this arena.”
The backbone of the conventional internet is a fiber optic network that relays bits of digital data as pulses of light. The MSU team will explore the cutting-edge technology needed to relay pairs of light particles called “entangled photons” that can encode information with mind-bending behavior explained by quantum physics — such as being able to interact with each other even when separated by large distances. Quantum computers operate on similar principles to perform certain tasks much faster than regular computers can.
The project will involve installing an experimental network on MSU’s Bozeman campus to test whether existing, specialized, multicore fiber optic cables, which were originally designed for high-capacity internet communication, can also convey the delicate quantum signals. “There are only a few other field trials like this in the world right now,” said Roudas, the department’s Gilhousen Telecommunications Chair.
The quantum internet isn’t intended to replace its conventional counterpart but rather to expand it so that regular and quantum computers can be interconnected using a single network. In addition, the quantum internet will enable a new level of security for online transactions and other confidential communications, according to Roudas. As things are now, determined hackers can stealthily read and copy the digital “keys” that encrypt data sent over today’s networks, but entangled photons would be disturbed by such eavesdropping, alerting users to compromised security. That means encryption keys can be reliably sent over quantum channels and then used to decipher encrypted data sent over the conventional internet. MSU’s experiments into doing this over multicore cables could help streamline development of the quantum internet and enable faster exchange of the quantum encryption keys over the multiple parallel channels. Additionally, a major focus of the project is exploring ways of sending data — not just encryption keys — in quantum form.
“There’s a huge worldwide effort on this, and there aren’t many labs that can do this kind of work,” said project member Krishna Rupavatharam, associate director of MSU’s Spectrum Lab, a photonics research lab under MSU’s Vice President for Research, Economic Development, and Graduate Education. Although some quantum networks are already operating, the technology is in its infancy, and MSU is uniquely positioned to develop some of the missing pieces, he said.
Since 1999, Spectrum Lab has served as a hub for advanced physics and engineering research that has spun off many of the private companies that make up Bozeman’s optics and photonics industry. Now, some of those technologies — such as materials that can precisely manipulate the properties of laser light — are showing promise for applications in the quantum internet, Rupavatharam noted.
“We’ve been a leader in these photonics materials for decades,” said Charles Thiel, a senior research scientist in the physics department and Spectrum Lab. Working closely with Rupavatharam, he will develop hardware that can receive and store the quantum signals, a critical component of the “quantum repeaters” needed to store, amplify and transport quantum signals over greater distances to make the quantum internet feasible. The work will expand on research that formerly took Thiel to faraway, specialized facilities for testing but that will now be possible at MSU because of the project’s experimental network.
“Being able to do this work at MSU allows us to play a much bigger role in this quantum effort,” he said.
Jarek Kwapisz, professor in the Department of Mathematical Sciences in MSU’s College of Letters and Science, will contribute advanced modeling and simulation and will help with designing algorithms for processing quantum signals. MSU has historical strength in the mathematical theory of dynamical systems that has new relevance for quantum research, according to Kwapisz.
“I’m excited to expand into this challenging new field,” he said. “This project is an unprecedented collaboration among MSU researchers in electrical engineering, physics and mathematics.” The project is aligned with a new seminar series called “Mathematics and Technology of the Second Quantum Revolution” that starts next spring and is focused on introducing undergraduate and graduate students to math skills involved in quantum research, he added.
The $6 million contract is through MSU’s Applied Research Lab, which opened in 2020 to enable work on energy- and defense-related research projects previously out of reach due to the lack of a secure facility. “This is a good example of how ARL can enable projects like this,” said Dan Miller, director of ARL. “We’re excited to have this opportunity to share MSU’s expertise in photonics and communications.”
Although the current work won’t happen at the Applied Research Lab, future phases of the project could involve expanding the quantum network to connect with the facility for more intensive testing, according to Roudas.
“Building this pioneering network infrastructure will put MSU at the forefront of this technological revolution in the coming years,” Roudas said.